Composition for staining and fireproofing wood.



SAMUEL CABOT, or sos'ron, MASSACHUSETTS.

COMPOS'lTlON FOR STAINING AND FI R EPROOFING WOOD SPEGEFIGATION forming part of Letters Patent No. 666,647; dated January 29, 1901.

Application filed June 22. 1900. S ial No. 21,219. (No specimens.)

To all whom it may concern:

Be itknown that. l, SAMUEL OABOT, a citizen of the United States, residing at Boston, in the county of Sutfolk and State of Massachusetts, have invented a new and useful 1mprovement in Compositions for Staining and Preserving \Vood, of which the following is a specification.

My invention relates to the art of staining and preserving wood; and it consists of an improved composition whereby wood or analogous fibrous materials may he stained, preserved, and at the same time rendered highly resistant to flame or radiated heat. Wood or analogous fibrous materials used in or upon buildings maynot only be given almost any desired tint by the use of this new composition, but will also be fire-resistant.

In-my United States Patent No. 29 ,568, is sued April 29, 1884, there is described a com- .position of matter useful in staining and preserving Wood, and in compounding the new composition which is the subject of this invention I prefer to use a stain such as is described in that patent. Other stains may be a used, however, and I do not wish to be understood as in any wise limited herein to the composition of matter described in my aforesaid patent. I refer thereto for a description of a stain which will serve admirably in the preparation of the new composition herein to -be described merely for the sake of brevity.

To prepare this new composition, I take a salt, preferably of a non-inflammable base, which'possesses the property of wasting away under the application of heat and passing into a vaporous or gaseous condition, either with or without actual chemical'dissociation of its elementary components. Volatile salts which disappear in vapor at a given temperature waste away without suit'ering such complete dissociation of components as do salts which, while not volatile in the strict sense, waste away by progressive dissociation of components. Of the salts'susceptible to wasting away under the influence of heat the latter classis, I believe, best adapted to fireprooling purposes, by reason of the protraction of the period during which the Wasting process takes place, although volatile salts are of value for the purpose. I comminute such a salt until it is in condition to mix thoroughly and intimately with a liquid stain and then mix the salt and the stain. The character of the salt selected for the purpose should be such that the salt will remain substantially permanent under ordinary conditions, and such also that it will pass into a'vaporous o'r gaseous condition at temperaturesbelow the ignition-point of the wood or other material to which the stain impregnated with the salt is to be applied. 'It' a stain such as the inflammable stains derived from petroleum is used, which lowers the ignition-point below that naturallg possessed by the material stained, the salt which is mixed with the stain should be of such a character as to pass into a vaporous or gaseous condition, either wholly or in substantial measure, at temperatures below the ignition-point of the stain used or that of the wood when impregnated with such a stain. Salts of this character which are soluble partially or wholly in water are not so effective as salts insoluble in water, for the reason that when wood or other building material treated with a salt-impregnated stain is exposed to the weather rain will dissolve away a soluble salt, even to a considerable depth in the material. Where the stained and fireproofed wood is used in unexposed. places, the solubility of the salt employed with the stain is not of so much consequence. The salts which I have found to be best adaptedto the uses aforesaid are those in which the base is non-inflammable and volatile at a temperature below that of the ignition of the material to which the stain is applied, while the acid or 'acids with which the base is combined to form the salts are volatile or dissociable at temperatures but slightly higher than the volatilizing-point oi the base.

Thus I employ any stain, preferably a creo sote-oil stain, such as described in my pat-entfound that ten per cent, by weight of sulfate of ammonium. and magnesium in creosote stain gives good results. If a stain colored used, care should be taken to select a salt which will notreact upon the coloring-matter to destroy or modify its effect, unless such modification is actually desired. The composition thus obtained will readily enter the pores. or grain of the material to be treated and will stain it effectively. At the same time the salt is carried into the pores or grain and distributed over the surface.

'lhecapacity of the salt to escape, either wholly or insubstantial measure, by .va'porization or transmission to a gaseous condition, either wholly. or in part by volatilization or progressive dissociation of its component elemen ts, renders it effective to reduce thetemperature of the material it it is exposed to heat, and thus decreases the inflammability of the material impregnated thereby.

\Vhat I claim, and desire to secure by Lettors Paton t, is

-l A new composition of matter consisting of a woo 1 -stain commingled with a salt susceptible of wasting away under the influence of heat at temperatures below the normal ignition-point of carbon.

2. A new composition of matter consisting of a wood-stain commingled with a salt of a non inflammable base, the said salt being susceptible of wasting away under the influence of heat at temperatures below the normal ignition-point of carbon.

3;. A new composition of matter consisting of a wood-stain commingled with a salt in soluble in water, and susceptible of wasting away under the influence ofheat. with pigments or other coloringmatter is 4. A new composition of matter consisting of a wood-stain commingled with a salt of a non-inflammable base, said salt being; insoluble in water and susceptible of wasting away under the influence of heat.

- 5. A new composition of matter consisting of a creosote-oil stain commingled with a salt susceptible of wasting away under heat.

6. A new composition of matter consisting, of a creosote-oil stain commingled with a salt of a non-inflammable base, the said salt being susceptible of wasting away under the influence of heat.

7. A new composition of matter consisting of a creosote-oil stain commingled with a salt insoluble in water and susceptible of wasting, away under the influence of heat.

8. A new composition of matter consisting" of a creosoteo'il stain com mingled with a salt of a non-inflammable. base, the 'said salt be ing insoluble in water and susceptible of wasting away under the influence of heat.

9. new composition of matter for stainingand fireprooiing wood, consisting of, a creosote-oil stain commingled with a basic sulfate of ammonium and magnesium."

Signed by me at Boston, lvlassachusetts, this 21st day of June, 1900.

SAML. CABO'I. Witnesses:

THOMAS M. YiNsoN, IVIAHTIN J. G1 I'JMARTTN. 

